You got banned from a channel. Nobody here is an op on that channel so we have no way of knowing why you were banned. Maybe you broke a rule on the channel, maybe you just happened to have a similar address to someone else who was causing trouble. The fact that the ban message mentions an "abusive subnet" suggests the ban mask might be quite wide because of a number of troublesome users from that section of IP addresses so its quite possible it wasn't meant to affect you. Once again though, we don't know because nobody here has any association with whatever channel this is. You need to contact one of the ops on that channel to get any further information and they are the only ones who can unban you. If they choose to ignore you there's nothing anyone here can do about that.
None of this has anything to do with the forum being any good or not, you're simply asking the wrong people.